1. Field of the Invention
The present invention relates to a method and a device for parting a laminated substrate used for a liquid crystal cell, which can be suitably employed for manufacturing, for example, a liquid crystal display device.
2. Description of Related Art
Generally, a process of manufacturing a liquid crystal display is classified roughly into three processes including a process of fabricating a color filter substrate and an array substrate (for example, Thin Film Transistor or TFT), a process of forming a cell containing a lamination of both fabricated substrates and a process of constructing a module into which a driver used for driving a cell or the like is embedded.
The lamination of the substrates contained in the processes of forming the cell is performed after processes including washing following a fabrication of each substrate, application of orientation films, rubbing, coating with sealing materials and mounting of a spacer are complete.
Since a large size substrate that can be chamfered on multiple faces is used to improve productivity in the processes, the large size substrate obtained after the lamination has to be parted, depending on a size of a product, into a plurality of substrates that can be used as liquid crystal cells.
FIGS. 10A and 10B are perspective views explaining a conventional method for parting the laminated substrate used for the liquid crystal cell. FIGS. 11A and 11B are front views explaining a scribing process and a breaking process in the conventional method for parting the laminated substrate used for the liquid crystal cell. As shown in FIGS. 10A and 10B and 11A and 11B, in the conventional method for parting the laminated substrate, when a laminated substrate 103, obtained by laminating a first substrate 101 on to a second substrate 102, is parted into a plurality of substrates that can be used as the liquid crystal cell, parting is performed, after a scribe line 101a (scribed groove) is formed on one of the two substrates constituting the laminated substrate 103, for example, on the substrate 101, by a parting force applied at one time to the other substrate, for example, on the substrate 102, in a position being directly above the scribe line 101a along a line being parallel to the scribe line 101a, using a squeegee 105.
However, the conventional method for parting the laminated substrate presents a problem in that, since the parting force has to be applied at one time, to the laminated substrate 103, the application of a comparatively large parting force is required for parting the laminated substrate 103. As a result, as shown in FIGS. 12A and 12B, when the laminated substrate 103 is parted, a parting line 106, due to a residual stress occurring after the formation of a pattern (sealing pattern) 107 in a pre-working process, cannot be made vertical to a face on which the scribe line 101a is formed and is bent on a side of the scribe line 101a, which thus causes a failure in the parting of the laminated substrate 103. Moreover, though technology of a “method for parting a panel” is disclosed in Japanese Patent Application laid-open Hei1-170880, it cannot solve the above problem because the parting process disclosed in the Application is performed by using “parting power applied at one time to a laminated substrate in a position being deviated by a predetermined distance from a directly upward position of a scribe line”.